While I/0 psychologists have traditionally viewed personality
testing as contributing little to the prediction of job performance,
recent development of the `big five' personality constructs has
shown that personality tests can be valid predictors of performance and
may add significant incremental validity to tests of cognitive ability.
The generality of these higher-order traits, however, may limit their
usefulness in a selection setting. Correlational data is presented from
a sample of police recruits (n=284) who completed the NEO Personality
Inventory-Revised early in their basic training. Both higher- and
middle-order traits were found to be linked to both broad and narrow
performance outcomes. Conscientiousness added incremental validity to
cognitive testing. The assessment of higher-order and middle-order
personality traits for personnel selection is discussed.

During the past three decades the view that personality is a poor
predictor of job performance has become established among many
occupational psychologists in New Zealand. Early reviews (Ghiselli &
Barthol, 1953; Guion & Gottier, 1965; and Mischel, 1968) that helped
shape this gloomy evaluation may have been overly pessimistic in their
conclusions. Many criticisms raised by early personality test reviews
(eg. Mischel, 1968) have been addressed and shown to be less significant
than previously thought, or have resulted in improved methodology (Hogan
& Nicholson, 1988). One such improvement is the development of
personality inventories designed to measure qualities among typical
individuals instead of psychopathology among the deviant or mentally
disordered. Guion and Gottier (1965) found that tests developed for
specific purposes were more predictive of performance than tests scored
with standardised algorithms. Personality tests designed to measure
"normal" behavioural traits are likely to improve the
development of logical links between job requirements, personality
measurement, and performance (Rosse, Miller, & Barnes, 1991).

During the last decade two developments have lead some researchers
to re-evaluate the potential validity of personality tests when
selecting personnel. First, there is increasing agreement among
personality theorists and researchers alike that personality can be
organised and classified within a `big five' structural framework,
also labelled the five-factor model (Norman, 1963). This has provided a
useful taxonomy in which to identify consistent and meaningful
relationships between personality traits and performance criteria for
different occupations. Secondly, the techniques of meta-analysis, which
Barrett (1992) coined the first wonder of personnel psychology, have
recently been applied to new reviews of personality and job performance.

The five-factor model of personality is based upon peer ratings
using ordinary trait vocabulary (Digman, 1990; Norman, 1963). While a
number of researchers have claimed to successfully identify a larger
number of major personality traits, these five traits or dimensions have
proved to be replicable over different theoretical frameworks, using
different instruments, and with ratings obtained from different sources,
a variety of samples, and with a high degree of generality (Barrick
& Mount, 1991; Conn & Ramanaiah, 1990; Costa & McCrae, 1990;
Goldberg, 1990).

These `big five' have traditionally been labelled Neuroticism
(vs. emotional stability), Extraversion (or surgency), Openness to
experience (alternatively viewed as culture or intellect),
Agreeableness, and Conscientiousness (or dependability). In brief,
Neuroticism is the inclination towards expressing anxiety, anger,
depression, and other negative affects. Extraversion is marked by
sociability, energy, and a buoyant frame of mind. Openness is
characterised by objectivity, need for variety, and curiosity.
Agreeableness is a tendency towards altruism, trust, and sympathy, and
Conscientiousness is characterised by self-discipline, order,
reliability, and foresight. The `big five' dimensions are
relatively independent of cognitive ability measures (McCrae &
Costa, 1987), and while not without controversy (Hershon & Gorsuch,
1988; Hough, 1992) the five-factor model provides a meaningful taxonomy
of traits comprising five relatively independent dimensions with
associated sub-factors.

Hunter and Schmidt (1990) and colleagues (cf. Schmidt, Hunter,
Pearlman & Hirsh, 1985) have presented persuasive evidence that both
disputes the situation-specificity hypothesis and increases the validity
of psychometric tests by accounting for the attenuation of results due
to statistical artifacts. The primary conclusion for personnel selection
is that cognitive ability generally predicts job performance better than
other predictors, therefore, it is the most cost-effective construct
worth measuring when selecting staff. Even with fully corrected validity
coefficients, however, a great deal of criterion variance remains
unaccounted for by cognitive testing.

Personality tests tap into performance variance beyond that which
can be explained by cognitive tests alone (Driskell, Hogan, Salas, &
Hoskin, 1994; Guion, 1987; Rosse et al., 1991). In a small sample of
accountants, Day & Silverman (1989) found that three personality,
scales were significant predictors of performance, even after
partialling out cognitive ability, while Schippman and Prien (1989) also
found support for personality as a predictor of performance among
managers. In one of the few studies to include both personality and
ability measures McHenry, Hough, Toquam, Hansom, and Ashworth (1990)
found two out of five military performance criteria (personal discipline
and physical fitness/military bearing) were better predicted by
personality and temperament than ability, as measured by the Armed
Services Vocational Aptitude Battery.

Barrick and Mount (1991) used multiple criteria and multiple
occupational groups in their review of the `big five' and job
performance. They found Conscientiousness to be a valid predictor of
performance across criterion type and occupational group (estimated true
r=.22), while results for the remaining factors varied depending upon
the specific occupation and criterion used. Extraversion was found to be
a valid predictor for managers and sales occupations (both involving
social interaction) across performance criterion, and along with
Openness was a valid predictor for the criterion of training proficiency
across occupations. Tett, Jackson, and Rothstein (1991), however, using
a confirmatory approach to study selection, found the highest corrected
mean validity of the "big five" to be for Agreeableness (.33).

Inconsistencies in research findings highlight the need for precise
and differentiated research on personality-job performance links
(Goldberg, 1993; Lord, De Vader, & Alliger, 1986). The poor validity
of many job performance measures, and summarising of criterion-related
validities across either predictor or criterion constructs, obscures the
usefulness of personality scales (Hough, 1992). Furthermore, the
relationship between personality and performance is susceptible to the
moderating variables of performance criterion and job type (Barrick
& Mount, 1991; Hulin, 1962; Nathan & Alexander, 1988; Tett et
al., 1991).

While the five-factor model and meta-analysis have demonstrated the
usefulness of personality for selection, the `big five' themselves
may in fact be too broad to have predictive usefulness among job
applicants (eg. Briggs, 1989; McAdams, 1992). Hough (1992) found nine
factors to be more appropriate than the "big five" whereas
Mershon and Gorsuch (1988) found evidence for 16 factors. Saville,
Nyfield, Sik, and Hackston (1991; cited in Schmit & Ryan, 1993)
found specific facets of the `big five' constructs were better
predictors than the broader global measures (eg. Conscientiousness), as
did Driskell et al. (1994).

Schmit and Ryan (1993) have identified an "ideal
employee" factor based upon work-related facets, further suggesting
that the `big five' model may be inappropriate for personnel
selection. Their ideal employee factor (Conscientiousness-plus) included
mainly Conscientiousness items but also items from the other four broad
dimensions. Personality tests designed to measure middle-level traits
within the big five (John, 1990) may better account for different
personality requirements between occupational groups (Schmit & Ryan,
1993) than instruments designed to only assess the broader `big
five' dimensions.

The appropriateness of whether occupational psychologists should
measure carefully a single narrowly defined variable or undertake a less
detailed exploration of many separate variables is the
bandwidth-fidelity debate (Cronbach & Gleser, 1965). Traditionally,
the focus of this discussion in personality assessment for personnel
selection has been whether broadly defined traits are better predictors
of behaviour than narrowly defined traits. As Ones and Viswesvaran
(1996) state, however, this has somewhat distracted the issue into an
either/or debate. There is nothing about broad traits that precludes
prediction of narrow behaviours, or vice-a-versa.

The level of specificity required in personality assessment for
personnel selection depends on the question and requirements asked of
the assessment process. On this basis alone it is doubtful if an
analysis of the overall validity of personality is meaningful (Schmitt,
Gooding, Noe, & Kirsch, 1984). Prediction and explanation of
broad-based behaviours would require adequate breadth in assessment
tools. Conversely, if the identification of narrow characteristics are
the express purpose as with developmental interventions for example,
higher fidelity would likely be more suitable (Hogan & Roberts,
1996).

Personality traits are likely to be differentially relevant
depending upon the specific job requirements (Campbell, McHenry, &
Wise, 1990). The use of narrow work outcome criterion in research may
misrepresent the usefulness of personality for selection. An extensive
and objective job performance criterion that encompasses many aspects of
performance would provide a more accurate reflection of performance and
be less susceptible to bias (Nathan & Alexander, 1988).

Police recruits (n=284) from the Royal New Zealand Police College
(RNZPC) who had completed their six month basic police training during
1995 were used for this study. Of these recruits 66% were male and 82%
caucasian, with a mean age of 28.

Measures

The NEO Personality Inventory -Revised (NEO PI-R; Costa &
McCrae, 1992), has been reviewed as one of the be:st measures of the
five-factor model developed to date (Briggs, 1992). The NEO PI-R
measures the `big five' factors of Neuroticism, Extraversion,
Openness, Agreeableness, and Conscientiousness and also 30 middle-order
personality traits (six middle-order traits embedded within each of the
`big five' factors) designed to identify individual variability
within the larger "big five" personality factors.

The NEO Personality Inventory - Revised consists of 240 items that
define 30 eight-item facet subscales over the five dimensions. Item
factor analysis recovered the five domain scales when five varimax
factors were extracted with correlations of .91, .89, .95, .95, and .89
for N, E, O, A, and C respectively. After varimax rotation all facets
have their highest loading on the intended factor with factor loadings
between facet scales and their appropriate domains of between .49 and
.81. Coefficient alpha's for the Form S (and Form R) domain scales
remain high at .92 (.93), .89 (.90), .87 (.89), .86 (.95), and .90 (.92)
respectively for N, E, O, A, and C. Coefficient alpha reliability's
for the 30 facet scales range from .56 to .81 for Form S and from .60 to
.90, and are adequate when considering their 8-item length.

The NEO PI-R has comprised part of the psychological test battery
for New Zealand Police selection since 1 April 1996. Study participants
formed part of the validation cohort used by Police prior to this
implementation.

The Pl/Pq Higher Test (New Zealand Revision), is a commercially
available cognitive ability test developed by the Australian Council for
Educational Research (De Lemos, 1988), designed to assess verbal and
numerical reasoning in adults who have completed their secondary school
education. It has formed part of the psychological test battery for
selection into the New Zealand Police since 1990. Kuder-Richardson
formula KR-20 has been reported at .92 and .91 for two samples of school
students (ACER, 1981), and alternate form reliability with the ACER
Higher Test ML/MQ is reported at .90 (ACER, 1981) and .81 (Dugdale,
1999). Adequate criterion-related validity is reported with scholastic
achievement and other tests of general mental ability (ACER, 1981) such
as the ACER Advanced Test B40 (r=.80, n=102). Test scores are
interpreted after transformation into stanines. Stanines divide scores
into nine levels determined by a normal distribution with a mean of 5.0
and a standard deviation of 2.0.

Performance was measured by the total score obtained in 17
practical (eg. self-defence, firearms) and academic (ie. paper and
pencil) tests completed by police recruits during the 22 week basic
training at the Royal New Zealand Police College (RNZPC). Test scores
were obtained on some of these 17 measures as examples of narrow
criterion, compared to overall performance as a broad criterion. These
skills and knowledge areas include police law and procedure, social
science skills training, physical education and self-defence, firearms,
driving, and computer studies. The mean overall performance score for
the study sample was 833 out of a possible 1000 (Sd = 42).

Procedure

During the first month of police basic training all participants
completed the NEO PI-R. All participants were informed prior to
completing the NEO PI-R, that they would receive confidential feedback,
and that their personal results would be used for research purposes only
and not to assess their job performance or suitability while undergoing
police training. Upon completion of the 22-week basic training course
the performance score achieved during basic training, and the pre-entry
cognitive test score, (Pl/Pq) was obtained for each participant.

Summary data for all measures in the current study are presented in
Table 1. The Pl/Pq cognitive ability test and the broader higher-order
trait of Conscientiousness were found to possess the highest correlation
with overall training performance (Table 2). Of the broader higher-order
traits, only Openness and Agreeableness were found to possess no
significant correlation with performance. Neuroticism was the only
higher-order trait to have a negative correlation with performance.

Correlations between the 30 narrow middle-order traits of the
NEO-PI-R and overall training performance are illustrated in Table 3.
Significant correlations with performance were found for the traits of
Self-discipline, Activity, Ideas, Competence, Achievement Striving,
Dutifulness, Order, Assertiveness, Trust, Impulsiveness, Vulnerability,
and Deliberation. Of note is that all six narrow middle-order traits
within the `big five' dimension of Conscientiousness were
correlated with performance. When comparing the use of broad
(higher-order) versus narrow (middle-order) personality traits using a
broad criterion, three of the `big five' were found to
significantly correlate with training performance (Table 2) compared to
12 of the thirty narrower, middle-order personality traits (Table 3).

The regression of multiple higher-order predictors upon performance
is shown in Tables 5 and 6. Predictors were entered in order of the
highest to lowest correlation with performance (Table 2). Of the four
predictors entered - cognitive ability, conscientiousness, extraversion,
neuroticism - only conscientiousness added significant incremental
validity to the measure of cognitive ability used, attaining a multiple
correlation of .42.

Both higher- and middle-order personality traits were found to be
significantly correlated with the performance of police recruits at the
Royal New Zealand Police College. Performance was found to be correlated
to narrower middle-order traits from all of the `big five'
higher-order traits (Neuroticism, Extraversion, Openness, Agreeableness,
and Conscientiousness). Police recruits who are reliable, dependable,
determined, self-confident and goal-oriented; prefer to be busy; are
willing to consider new ideas and perspective's; are forceful and
assertive when required; possess a belief that society is generally
honest and of good intention; possess a tolerance for personal
frustration; and are resistant to stress, are likely to be higher
performers during training.

The broad higher-order trait of Conscientiousness possessed the
strongest relationship with performance and both the higher-order traits
of Neuroticism and Extraversion were correlated with performance in the
direction expected. These findings are supported by Barrick and Mount
(1991), who identified extraversion, emotional stability, agreeableness,
and conscientiousness as being important personality factors for police
performance across criterion type (estimated true correlations ranging
from .09 to .22). Cortina, Doherty, Schmitt, Kaufman, and Smith (1992)
using the MMPI and IPI to measure the `big five' also correlated
these factors with training success, peer ratings, probationary ratings,
and turnover in a police sample. The current study found no support for
a link between Agreeableness and police training performance. However,
narrower middle-order traits from both Agreeableness and Openness were
identified in this study as being related to performance, the latter
having been linked by Barrick and Mount (1991) to training proficiency.

The police recruit sample used for this study was not a sample of
job applicants, and applying these results in terms of appropriate
bandwidth-fidelity of personality measurement to other occupational
contexts requires caution. Schmit and Ryan (1993) found that the
five-factor model fitted a student sample but not a sample of job
applicants. This may be due to measurement of the broad higher-order
`big five' alone, rather than middle-order traits embedded within
the five-factor model, along with variable motivation for impression
management. Selection of job applicants using personality tests should
ideally include combinations of specific job relevant items or scales
from each dimension of the `big five'. As the current study
illustrates, there may be little practical difference in using a large
range of narrow personality traits or a smaller range of broad ones.
Rather than bandwidth or fidelity, the issue for personality measurement
in personnel selection is one of matching suitable personality traits to
job content.

It is reasonable to expect that different personality traits are
important within different occupational contexts (Bolton, 1985). This
increases the importance of primary research across job type and job
role, using middle-order and higher-order personality trait scales, with
various criterion. The combination of higher-order (broad) and
middle-order (narrow) assessment used in the current study reveals links
between personality and a variety of performance criteria, that would
remain hidden using the `big five' alone. The narrow focus on
single traits in isolation from others has been criticised by Smith
(1994), and Robertson (1993) has drawn attention to the possibility of
complex rather than linear relationships between personality and job
performance. For example, the influence of personality upon job
performance at entry-level may change as an incumbent's career
progresses either horizontally or vertically.

Pugh (1985), for example, found striving for status as the best
predictor after 2 years but that after 4 years the best predictors of
police job performance became that of a stable, responsible, and
socially skilled individual. This suggests that early in a police career
new recruits may focus upon fitting in with police culture (membership
status) but that as their position stabilises police work becomes more
important than status among colleagues. Unfortunately, police
personality research tends to involve small sample sizes (less than 100)
and the use of tests that are not easily comparable (eg. Hiatt &
Hargrave, 1988; Pugh, 1985). Methodological constraints have made it
difficult to determine what personality traits are related to police
performance rather than a lack of predictive validity for personality
per se (Hogg & Wilson, 1995).

The application of personality assessment to job performance is
therefore likely to vary depending upon the requirements of the job and
measurement factor's. Conscientious employees are an asset to every
organisation and the nature of police work, requiring extensive contact
and interaction with the public, indicates the importance of elements
within the dimension of Extraversion. Perhaps, also, the dimension of
Agreeableness, which is the higher-order trait most reflective of
cooperation and empathy. Neurotic individuals may become dissatisfied
easily, have lower self-esteem, and be likely to perform less
effectively under situations of stress (Little, Lecci, & Watkinson,
1992).

This study, using a broad job performance indicator, has
demonstrated that personality traits based upon the broad `big
five' contribute incremental predictive validity when combined with
cognitive ability measures. It also supports the benefit, when selecting
personnel of using the NEO PIR and its combination of higher- and
middle-order personality traits. Future research needs to examine the
link between personality and narrower on-the-job performance measures,
and whether the personality traits found to contribute to job
performance as a recruit will remain valid predictors of job performance
during a police career.

Hershon, B., & Gorsuch, R.L. (1988). Number of factors in the
personality sphere: Does increase in factors increase predictability of
real-life criteria? Journal of Personality and Social Psychology, 55(4),
675-680.

John, O.P. (1990). The "Big Five" factor taxonomy:
Dimensions of personality in the natural language and in questionnaires.
In L.A. Pervin (Ed.), Handbook of personality theory and research (pp.
66-100). New York: Guilford Press.

Schippman, J.S. & Prien, E.P. (1989). An assessment of the
contributions of general mental ability and personality characteristics
to management success. Journal of Business and Psychology, 3, 423-437.